Exporting a small area of a large map at high resolution

It could be I’m missing an important feature but if not, please can it be considered for a future release?

For an experiment last weekend I surveyed my home village and uploaded 2,000 nadir images for which DD has done a good job of creating a 2d map. When I have gone to export an orthomosaic at it’s highest available resolution, I receive a notification saying its size is too big to export. Understandably, the file size would be monstrous with it covering 400+hectares but instead of allowing me to export a small area of a particular spot, I’m forced to upload the images again and purposely create a smaller map that will allow me to export the smaller area. Is this right?

It seems a bit backward that firstly we should need to spend several further hours/days processing additional smaller maps to duplicate something we’d already have, but more so that DD would need to store duplicate images on their server just to allow us to export sections of a wider map separately.

Am I missing something or is there really no way of exporting a small area of a large map? Instead of uploading 8Gb of photos say, it could be I end up uploading a total of 30Gb. Surely 8Gb makes more sense in terms of DD’s storage facility?

Thanks for your help.

James.

I think that the only thing you are missing is that our capability far outweighs current hardware capability, especially in the sense of a shared farm. This is why some people like local processing better, but that could take days. In a situation like this I am totally fine with uploading 4 maps then stitching them together in QGIS or Microsoft ICE.

DD is able to process 400 hectares eithout a problem so I would have assumed the hard work was already over. All I’m asking is that we be able to cut a slice out of it but maybe that’s easier said than done. Just like a high res print screen, and believe me was very tempted in order to save multiple processes.

Just needs a crop/export tool.

Oh, ok. I’ve never tried something that large so I misunderstood. So you are basically wanting to export a region of the map at the highest resolution possible? Without having to open the images in a 3rd party program and crop yourself? Interesting, but if I already have the full-res exported I don’t see an issue opening it in a program like GIMP, cropping and saving as. Just took me less than one minute.

That’s the thing @MichaelL, I can’t export the processed map at high res. DD says it’s too big to export. Instead, the only workaround I can find is to process additional maps of the smaller areas and in doing so uploading additional tens of Gb which seems crazy for both me and DD. How long can their storage facility sustain that for?

I perfectly understand why it’s too big to export and I probably wouldn’t even attempt to if I were given the opportunity, but it would be nice to be able to export a smaller area of the already processed map. As you say, if I’d already exported the larger map I could simply use PS or similar to crop it in seconds but I can’t even get that far.

Cheers.

That’s why I originally suggested the map be processed in separate sections. Opening each piece would also be easier and you can cut out the section you want in the software I mentioned. You can combine the piece as well for a super map.
Another option is to reprocess with only the section you want outlined. It will disregard the images outside the perimeter and process much faster.
All this is suggested as a workaround for the lack of the capability you diesire.

If DD can cope with the large process, as it did, it seems daft that we should next need to make additional maps just so I can export smaller areas from it. In this instance, I don’t know I want a particular area until I need it and so I would then have to ensure I have access to the images and an internet connection with a high bandwidth before waiting a few additional hours also to export.

Far easier to just add a crop tool and to be honest I couldn’t believe something so obvious wasn’t already available. I was almost certain I’d missed something and nearly didn’t raise it at all through fear I’d look stupid when someone far cleverer presented me with it.

Have you tried this Cropping tool as described on the FAQ page. Crop it down and try exporting that.

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And there it is. Thank you Gary. You are that more cleverer person.

Gary, once I’ve cropped and exported etc, which I have just carried out successfully, is there any way to get the marquee to revert back to its original position? I note it saves live with every modification to each anchor.

Thank you again. I will now delete my unnecessary maps.

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You just have to recrop it larger to the original position.
You can crop different sections and export. The whole map is still there when you recrop larger.

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That’s what I assumed Gary. Thank you.

To save me trying unnecessarily right now, when I export a jpg larger than the extent of detail, will I be left with a huge white border in export or will it reduce the white to minimum as it would normally do?

Hi @JamesC,

To answer your additional question, when using our Cropping tool the export size will be adjusted to your cropped extension, meaning that the export should not include any huge white borders. Please give that a try :slight_smile:

Happy mapping!
Andrea

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Nice, wish I would have seen this a long time ago! Thanks Gary.